Pilot and burner control apparatus



Au 15, 1933. F A, GAU R ET AL 1,922,201

PILOT AND BURNERCONTROL APPARATUS Original Filed May 29 1925 2 Sheets-Sheet 1 I N VEN TOR.

- ATTORNEY.

Aug. 15, 1933. F. A. GAUGER ETAL I PILOT -AND BURNER CONTROL APPARATUS 2 Sheets-Sheet 2' Original Filed May 29,1925

Y INVENTOR.

' ATTORNEY.

Patented Aug. 15, 1933 1,922,201 PILOT AND BURNER CONTROL APPARATUS Frank A. Gauger, Boy W. Johnson, and Arthur Neuser, Milwaukee, Wis., assignors, by mesne assignments, to Minneapolis-Honeywell Regulator Company, Minneapolis, Minn., a Corporation of Delaware Original application May. 29, 1925, Serial No."

Divided and this application July 18,

1927. Serial No. 206,725

14 Claims. (Cl. 158117.1)

This invention relates to improvements in pilot and burner control apparatus, and more espez iially to such. apparatus adapted for use in connection with gas appliances having gas burners therein, the present application being a division of our co-pending application for pilot and burner control apparatus, filed May 29, 1925, Serial No. 33,698. 1

For the purpose of illustrating our invention,

we have here shown a gas appliance which is a water heater. It is to be understood, however, that our invention may be used with other forms of gas appliances or heaters. The apparatus is especially adapted for use in connection with gas appliances in which the main burner is somewhat enclosed by a casing, housing or otherwise. In practically all gas appliances there is provided such a casing or housing for the purpose of confining the heat.

By the use of our invention, we are enabled to use a Bunsen pilot light and thus provide a blue smokeless flame. The apparatus is so constructed also that the concussion occurring upon the ignition of the main burner does not extinguish the pilot light.

Another feature of our invention is the provision of a single valve which acts both as a safety valve and also regulates the gas or fuel supply to the main burner.

Our apparatus is also so constructed that the thermostat forming a part of the apparatus is protected from cold drafts of air such :as frequently may be found in basements where gas appliances are installed. 1

5 Other features and advantages of our invention will appear more fully as we proceed with our specification.

In that'form of device embodying the features of our invention shown in the accompanying drawings, Figure 1 is a view in sideelevation of a gas appliance such as, vif or example, a gas water heater, showing the same equipped with our improved pilot and burner control apparatus; Fig. 2 is a vertical sectional view showing the thermostat, pilot, gas valve, and related parts; Fig. 3

is a view taken as indicated by the line 3 of Fig. 2; and Fig; 4 is a fragmentary view in elevation showing the fulcrum arrangement for the lever. r As shown in the drawings, 10 indicatesthe housing or casing of a gas appliance such as, for example, a water heater 'having therein the usual water coil 11. Below the water coil is arranged, in the usual manner, the main gas burner 12 to which gas or other suitable fuel is ad however, we may state that this time control mitted through the pipe 13. 14 indicates the main gas supply pipe which supplies fuel both to the pilot and the main burner.

. 15 indicates, in general, a member here shown as a box-like casting adapted to house the gas v 0 valve and also serving as-a support at its upper end for the pilot tube and thermostat. As shown in Fig. 2, the fuel pipe 14 enters the casting 15 at one side permitting gas to enter the chamber 16. From the chamber 16 a port 17 leads to the end of the pipe 13 which goes to the burner 12. It will be seen that gas coming from the fuel pipe 14 must pass through the port 17 to reach the burner 12. The port 1'1 is controlled by a valve 18 provided with a valve stem 19 as shown. A spiral spring 20 tends to hold the valve 18 open.

We will now describev the apparatus used for controlling the valve .18 during theordinary operation of the gas appliance, assuming that there has been 'no failure of the pilot light.

Opposite to the valve 18 is arranged a slida'ble plunger 21 which is urged inwardly, that is,

provided with an annular groove 23 in which is fitted the forked end 24 of the bell crank lever 25 which is pivoted at 26. The arm 27 of the bell crank lever has attached at its outer end a weight 28 tending to pull the arm 27 downwardly because of the force of gravity.- Also attached to the arm 2'7 is a wire or cable 29 leading upwardly to a time control mechanism 30. Interposed in the wire or cable 29 is a a spiral spring 31 for-the purpose of absorbing Jars. The time control mechanism 30 is not shown or described in-detailas the same (per se) comprises no part of the present invention. For the purpose of understanding the construction and operation of the rest of the apparatus,

apparatus may comprise clockwork mechanism (such as is shown and described in the patent to Frank A. Gauger and Roy -W. Johnson for heater lighters, granted December 13, 1927, No. 1,652,524), adapted to be set to release the wire 29 at a predetermined time. It will be seen that, upon the release of the wire 29, the weight 28 will rock the bell crank lever to force in the plunger 21 and close the valve 18. When the gas appliance is burning, the valve 18 is open. The apparatus '30 is set so that, at the-desired time, the wire 29 will be released, permitting the weight 28 to drop, thereby closing the valve 18 and shutting 0115 the gas from the main .burner. It is to be understoodthat the time 'at 38 is joined to the casting 15.

control mechanism 30 includes a manually operable device or means equipped with an actuating handle whereby the wire or cable 29 is tensioned to permit the opening of the valve 18. The clock-work mechanism which is set by a winding handle 102 acts to r'eleasably secure manually operable device in position to maintain the valve open for a predetermined time. After the expiration of the selected time the clock-work mechanism releases the manually operable device and thus the tension on the cable 29 is released and the valve is closed.

Means are also provided whereby the valve 18 will be closed in the event the pilot light goes out. In general, such means include a thermostat kept hot while the pilot light is burning. Upon failure of the pilot light, the thermostat cools and thereby closes the valve 18. 32 indicates the Bunsen pilot tube having the flame end 33 inside of the gas supply casing 10 and over the main burner 12. Arranged above the Bunsen pilot tube is a thermostat comprising the tube 34 having inside of it the rod 35. In the end of the tube is a plug 36 against which the end of the rod 35 rests. The tube and rod are made of different metals, having different coefficients of expansion. For example, tube 34 may be copper and the rod 35 some other metal that does not expand so rapidly. Attached to the end 36 of the tube 34 is a cap 37 which lies inside of the gas appliance casing 10 just above the pilot flame at the end 33 of pilot 32 so that the burning of the pilot will keep the cap 3'7 hot. The outer end of the tube 34 as indicated The rod 35 however, is somewhat longer and has its end 39 projecting out through a suitable hole in the casting 15 and provided at its end with a slight depression. Attached to the outer side of the casting 15 is a fulcrum bracket 40 carrying the fulcrum 41 against which is balanced the lever 42. 43 -indicates a nut having a pair of knife edges 44 engaging the inner side of the lever 42. The knife edges 44 are slightly below the fulcrum. 41. The nut 43 carries an adjusting screw 45 having its inner end reduced and resting in the depression at the end 39 of the rod 35. The lower end of the lever 42 is forked as indicated by'46 and embraces the valve stem 19. A spring 47 urges the lower end of the lever 42 inwardly. It will be seen that the offsetting of the fulcrum 41 and 44 causes movement of the lever 42 outwardly (as viewed in Fig. 2) when the end 39 of the rod 35 moves outwardly. Such movement of the rod is caused by contraction of the tube 34 upon cooling, and vice versa. The outerend of the valve stem 19 is somewhat reduced in'diameter as indicated by 48 and a washer 49 is held against the shoulder thus formed by means of a spiral spring 50.

In normal operation with the pilot light burning the valve 18 remains open unless it is closed by means of the plunger 21. The parts are so proportioned and adjusted that the heat from the pilot flame against the cap 37 keeps the tube 34 sufficiently hot and consequently lengthened so that the end 39 of the rod 35 is held in sufficiently so that the forked end 46 of the lever 42 is held in far enough, as shownin Fig. 2, so that the valve 18 remains open. If the pilot light goes out, the cap 3'7 and tube 34 cool, and the latter contracts. This forces the'end 39 of the rod 35 outwardly, to the left, (as viewed n Fig. 2) thus swinging the fork 46 of the lever 42 outwardly against the washer 49 to move the valve 18 to the left and thus close the same thereby shutting off all gas to the main burner. The spring 50 is stiff enough to overcome resistance of the spring 20 so that as lever 42 moves to the left the valve 18 will be closed.

Means are also provided so that a Bunsen pilot light can be used without danger of the same being extinguished from the concussion caused by the lighting or extinguishing of the main burner. A Bunsen flame is preferable to the ordinary carbon flame as it is practically smokeless and considerably hotter. Heretofore, however, difficulty has been experienced in using a small Bunsen pilot due to the fact that the gas coming through the pilot orifice is of such a smallamount that it has practically no velocity. In the Bunsen type of burner there is an air inlet adjacent to the gas orifice. Heretofore, when it was attempted to use the Bunsen pilot it was found that when the concussion accompanying the lighting or extinguishing of the main burner took place, such a draft of air was carried through the Bunsen tube as to put out the pilot light. In our device, we have surrounded the entire .Bunsen tube ,and also the thermostat by the air tube 51 which has its inner end 52 lying inside of the gas appliance housing or casing 10. It will be seen that the inner end of the Bunsen tube and the cap-37 of the thermostat project slightly beyond the end of the tube 52. 53 indicates the air inlet in the Bunsen tube 32 and 54 the gas orifice or jet. It will be seen that by means of this construction air entering the inlet 53 comes from the inside of the tube 51 which has its open end lying inside of the casing 10. Thus when there is a concussion in the heater the pressure at the end of the tube 52 is the same as that in the pilot tube 33. Consequently when such concussion occurs, there is no rush of air through the pilot tube 32 and consequently no disturbance of the gas supply coming out of the orifice 54. In other words, the air pressure is balanced in both directions so that a concussion does not interfere with the flow of the pilot gas supply.

The tube 51 also serves to protect the thermostat from cold drafts which frequently occur in basements and similar places where gas appliances are often installed. I

It is to be noted that by the use of our invention only one valve 18 is provided which acts as a safety valve for the pilot and also serves to regulate the gas supply.

It will be seen also that dropping of the weight 28 permits the spring 22 to move the plunger 21 to close the valve 18 and that the forked end 24 of the bell crank lever also operates to move the plunger 21. 55 indicates a gas supply pipe connected to the pipe 14 and adapted to supply gas to the Bunsen pilot light.

While we have shown and described certain embodiments of our. invention, it is to be understood that it is capable of many modifications. Changes, therefore, in the construction and a1- rangement may be made without departing from the spirit and scope of the invention as disclosed in the appended claims, in which it is our intention to claim all novelty inherent in our invention as broadly as possible in view of the prior art.

The invention claimed is: 1. In combination with a ,gas appliance having a main burner therein; a gas supply lead.-

" ing to said main burner; a valve controlling said gas supply; time control apparatus for control ling said gas valve; a pilot burner arranged .adjacent said main burner; and means whereby pilot tube lying within said first mentioned tube having its flame end inside of the gas appliance; a thermostat also lying within said first mentioned tube having one end inside of the gas appliance and adjacent the flame end of the pilot tube; and a connection between said thermostat and the gas valve whereby cooling of the thermostat caused by failure. of the pilot burner will cause a closing of the gas valve.

3. In combination with a gas. appliance having a main burner therein, a gas supply leading to said main burner, a single valve controlling the supply of gas to the main burner, a pilot burner in cooperative .relation to the main burner, means for biasing the valve to open position, manually operable means positionable to close said valve and also positionable to permit the valve to open, and thermostatic control means influenced by the heat of the pilot burner and associated with the valve to maintain it closed irrespective of the position of the manually operable means when the pilot burner is extinguished, said thermostatic control means leaving the valve free to open and close under the control of the manually operable means as long as, the pilot burner is lighted.

4. In combination with a gas appliance having a main burner. therein, a. gas supply leading to said main burner, a pilot burner in cooperative relation to the main burner, thermostatic control means influenced by the heat of the pilot burner, distant controlgmeans and a single valve controlling the gas supply to the main burner and subject to the action of the thermo-- "static means and also to the action of the distant control means, said distant control means being inoperative to open the valve when the light in the. pilot burner is extinguished.

5. In combination'with a gas appliance having a main burnertherein, a gas supply leading to said main burner, a single valve controlling the supply of gas to the main burner, a pilot burner in cooperative relation to the main burner, thermostatic control means influenced by the heat of the pilot burner and associated with the valve to maintain it closed when the pilot burner is extinguished, while leaving it free to open as long as the pilot burner is lighted, means for biasing the valve to closed position, a manu ally operable device located at a point distant with respectto said burner and/said valve and adapted to be operated to provide for the opening of the valve, and .a time element associated with the manually operable device and settable to allow the valve to remain open for a predetermined Period.

, wherein the valve is permitted to 6. In combination with 'a gas appliance having a main burner therein, a gas supply line leading to said main burner, a single valve'controlling the supply of gas to the main burner, means for biasing the valve to open position, a pilot burn- 30 er in cooperative relation to the main burner, thermostatic control means influenced 'by the heat of the pilot burner and associated with the valve to maintain it closed when the pilot burner is extinguished while 'leaving it free to open as long as the pilot burner is lighted, a I plunger positionable to engage the valve to keep it closed, and also positionable to leave' the valve free to open, and a manually operable device coacting with the plunger to position it in either of its valve opening or valve closing positions as may be" desired.

7. In combination with a gas appliance having a main burner therein, a gas supply line leading to said main burner, a single valve cone trolling the supply of gas to'the main burner, means for biasing the valve to open position, a pilot burner in cooperative relation to the main burner, thermostatic control means influenced by the heat of the pilot burner and associated coacting with the plunger to set the same in either of its valve opening or closing positions as may be desired, and including a time element settable to maintain the plunger in a position remain open for a predetermined period.

8. In combination with a gas appliancehaving a main burner, a gas supply leading to said main burner, a single valve controlling the supply of gas to'the main burner, a pilot. burner in cooperative relation to the main burner, thermostatic control means infiuenced by the heat of the pilot burner and associated with the valve to close it and prevent it from being'opened when the pilot burner is extinguished, while leaving it free to open as long as the pilot burner is lighted, a spring cooperable with the valve and tensioned to'open the same when the'valve is free'to open, and manually controllable means for closing the valve.

9. In combination with a gas appliance having a main burner, a gas supply leading to said main burner, a single valve controlling the supply of gas to the main burner, a pilot burner in cooperative relation'to the main burner, thermostatic control means influenced by the heat of the pilot burner and associated with the valve to maintain it closed when the pilot burner is extinguished, while leaving it free to open as long as the pilot burner. is lighted, a spring 00- operable with the valve and tensioned to open the same, manually controllable means for clos-. ing the valve including a plunger engageable with the valve, cable means operatively connected with the plunger, means located at a distant point of control for tensioning or releasing the cable means, and a time element associated with the means for tensioning or releasing the cable means and operable to hold the cable means tensioned for a selected period.

10. In combination with a gas appliance having a main burner, a pilot burner, and means for supplying fuel to the main burner, a single valve tor controlling the supply of fuel to the main burner, manually controllable means for regulating the opening and closing of said valve, said manually controllable means being positionable to provide for opening of the valve, and thermostatic means associated with the pilot burner and with the valve adapted to maintain the valve closed should the pilot burner become extinguished irrespective of the action of the manually controllable means.

11. In apparatus of the type having a pilot burner, a gas supply line and a valve in the line, the combination of a thermostatic element associated with the pilot burner to be influenced by the heat thereof and mechanism actuated by the thermostatic element for operating the valve, said mechanism including a lever having a movable end adjacent to the valve, yieldable means for urging the valve to open position, and yieldable means of greater strength than the first mentioned means tending to maintain the valve in closed position, said lever being adapted to render said second named means ineffective when the lever is in a predetermined position with respect to the valve.

12. A unit of the character described includinga pilot burner, a gas supply line having a valve therein and thermostatic control apparatus influenced by the heat of the pilot burner for operating the valve, said apparatus including means associated with the valve for urging it to open position, a lever adapted to be moved by a thermostatic element to control the operation of said means and a spring for transmitting motion from said lever to said valve, the

arrangement of said lever and spring being such that the spring opposes the force exerted upon the valve by said means in one position of the lever and permits said means to open the valve in another position of the lever.

13. In apparatus of the type having a pilot burner, a gas supply line and a valve therein, the combination of a thermostatic element associated with a pilot burner to be influenced by the heat thereof and means actuated by the thermostatic element for operating the valve, said means including a lever having an end adjacent a stem on the valve, a spring for urging the valve to open position and a second spring mounted on the valve stem and engageable by the lever when the lever is moved against said second spring so as to close the valve and a shoulder on the valve stem to take the thrust of the second spring when free of the lever so that the first spring may open the valve without interference by the lever.

14. In combination with a gas appliance having a main burner, a gas supply leading to said main burner, a valve controlling said gas supply, a tube having one end open and its other end closed and disposed with its open end communicating with the interior of the gas appliance, a pilot tube located in said first mentioned tube and having its flame end inside of the gas appliance, a thermostat disposed in the first tube and located adjacent the pilot tube to be subject to the heat of a flame therefrom, and means operable through the thermostat when cooling as on failure of the pilot burner to effect closing of the gas valve.

FRANK A. GAUGER. ROY W. JOHNSON. ARTHUR NEUSER. 

